//
//  main.cpp
//  20.有效的括号
//
//  Created by Yan Zihao on 2024/10/18.
//
#include<stdio.h>
#include<stdlib.h>
#include<stdbool.h>
#include<assert.h>

typedef int STDataType;

typedef struct Stack
{
    STDataType* a;
    int top;
    int capacity;
}ST;

// 初始化和销毁
void STInit(ST* pst);
void STDestroy(ST* pst);

// 入栈  出栈
void STPush(ST* pst, STDataType x);
void STPop(ST* pst);

// 取栈顶数据
STDataType STTop(ST* pst);

// 判空
bool STEmpty(ST* pst);
// 获取数据个数
int STSize(ST* pst);

// 初始化和销毁
void STInit(ST* pst)
{
    assert(pst);

    pst->a = NULL;
    // top指向栈顶数据的下一个位置
    pst->top = 0;

    // top指向栈顶数据
    //pst->top = -1;

    pst->capacity = 0;
}

void STDestroy(ST* pst)
{
    assert(pst);

    free(pst->a);
    pst->a = NULL;
    pst->top = pst->capacity = 0;
}

// 入栈  出栈
void STPush(ST* pst, STDataType x)
{
    assert(pst);

    // 扩容
    if (pst->top == pst->capacity)
    {
        int newcapacity = pst->capacity == 0 ? 4 : pst->capacity * 2;
        STDataType* tmp = (STDataType*)realloc(pst->a, newcapacity * sizeof(STDataType));
        if (tmp == NULL)
        {
            perror("realloc fail");
            return;
        }

        pst->a = tmp;
        pst->capacity = newcapacity;
    }

    pst->a[pst->top] = x;
    pst->top++;
}

void STPop(ST* pst)
{
    assert(pst);
    assert(pst->top > 0);

    pst->top--;
}

// 取栈顶数据
STDataType STTop(ST* pst)
{
    assert(pst);
    assert(pst->top > 0);

    return pst->a[pst->top - 1];
}

// 判空
bool STEmpty(ST* pst)
{
    assert(pst);

    return pst->top == 0;
}

// 获取数据个数
int STSize(ST* pst)
{
    assert(pst);

    return pst->top;
}

bool isValid(char* s)
{
    ST st;
    STInit(&st);
    while(*s)
    {
        //左括号入栈
        if(*s == '(' || *s == '[' || *s == '{')
        {
            STPush(&st, *s);
        }
        //右括号取栈顶尝试匹配左括号
        else
        {
            if(STEmpty(&st))
            {
                return false;
            }
            char top = STTop(&st);
            STPop(&st);
            if((top == '(' && *s != ')')
            ||(top == '[' && *s != ']')
            ||(top == '{' && *s != '}'))
            {
                STDestroy(&st);
                return false;
            }
        }
        ++s;
    }
    //栈不为空,说明左括号比右括号多,数量不匹配
    bool ret = STEmpty(&st);
    STDestroy(&st);
    return ret;
}

int main(void)
{
    char s[] = "[])";
    int flag = isValid(s);
    if(flag == 1)
    {
        printf("true\n");
    }
    else
    {
        printf("false\n");
    }
    
    return 0;
}
